Materials and Methods:
Sodium alginate (NaAlg), N-isopropyl acrylamide (PNIPAM), Graphite was purchased from Aldrich chemicals co. U.S.A., H3PO4, K2HPO4, CaCl2, KH2PO4, K2S2O8, KMnO4, H2O2, NaNO3, H2SO4, HCl, NaOH, and acetone, were purchased from s.d. fine chemicals Mumbai, India. 5-fluorouracil (5-FU) purchased from Himedia chemicals, India. All the above chemicals and distilled water were used entire the synthesis work.
Preparation of graphene oxide (GO):
Graphene oxide was prepared based on the modified Hummer’s method [37, 38]. Graphite (5g) was taken in a three neck round bottom flask (250mL) and cooled at 0°C for 1h. H2SO4 (115mL) is added into the graphite and stirred slowly followed by the addition of NaNO3 (2.5g)…show more content… 4% of sodium alginate was prepared and mixed with PNIPAM (1g) to prepare 5wt% polymer to blend solution. Different amounts of GO (2, 4, and 6wt%) were added then stirring for 24h in order to get a homogeneous solution. The GO/PNIPAM/NaAlg blend dispersions with various amounts of GO is shown in Figure 1(A). The homogeneous blend solution drops were then added via syringe, into gellant bath (50mL) of 2% CaCl2 solution (20:80; water: methanol) for 30min under constant stirring and then formed beads. The obtained composite beads were washed several times with water to remove surface adheres free calcium ions. Then the beads were dried at 40oC for 48h and were stored in desiccators for further analysis. NaAlg beads without PNIPAM and GO were also prepared. For formulations of pure NaAlg, NaAlg/PNIPAM, and NaAlg/PNIPAM-GO (2, 4, and 6wt%) composite beads were designated as S, SP, SPGx, SPGy, and SPGz respectively. Digital photographs of the resulted composite beads are shown in Figure…show more content… To prepare the pellets by using the beads were grinded with KBr under a hydraulic pressure of 700dynes/m2 and FTIR spectra were scanned range from 4000 to 400cm-1.The X-ray diffraction (X-RD) analysis of beads for all formulations was noticed by using a Rigaku Geiger flex diffractometer (Tokyo, Japan) furnished with Ni-filtered CuKα radiation of wavelength is 1.5418Ao. The dehydrated beads of similar size were seated on a sample holder. That the patterns were recognized in the range from 1.2 to 300 at a rate of scanning 10/min. The morphological images of composite beads were observed by scanning electron microscopy analyzer (SEM Table-top mini, SNE-3000M). Transmission electron microscopy of high-resolution analysis (HR-TEM, JEOL JEM-2010) was performed at an accelerating voltage of 200kV. The aqueous dispersion of GO was dropped onto the copper grid and dried at ambient temperature after that excess of moisture removed using a filter